The main focus of this research program will be the development of new methodology for the synthesis of pharmacologically important alkaloids. Emphasis will be placed on the preparation of natural products and their analogues which exhibit cardiovascular activity. These compounds include ergots (vasodilators), decahydroisoquinolines and quinolines (antiarrhythmics). These synthetic goals will be accomplished by utilizing the ability of the azabutadiene containing heterocycle, oxazole, to undergo 4 plus 2 cycloaddition reactions with dienophilic components to furnish substituted pyridines. The development of new techniques for the appendage of oxazoles to cyclic and acyclic systems will facilitate the generation of the necessary synthetic precursors. Because of the versatility of the Diels-Alder process, the facile preparation of an array of analogues for structure-activity studies will be possible.